title: A mouse translocation associated with Caspr5-2 disruption and perinatal lethality.
abstract: We have previously described the paralogous mouse genes Caspr5-1, -2, and -3 of the neurexin gene family. Here we present the cytogenetic and molecular mapping of a null mutation of Caspr5-2 which was caused by reciprocal translocation between chromosomes 1 and 8 with breakpoints at bands 1E2.1 and 8B2.1, respectively. The translocation disrupts Caspr5-2 between exons 1 and 2 and causes stillbirth or early postnatal lethality of homozygous carriers. Because no other candidate genes were found, the disruption of Caspr5-2 is most likely the cause of lethality. Only rarely do homozygotes survive the critical stage, reach fertility, and are then apparently normal. They may be rescued by one of the two other Caspr5 paralogs. Caspr5-2 is expressed in spinal cord and brain tissues. Despite giving special attention to regions where in wild-type fetuses maximum expression was found, no malformation that might have caused death could be detected in fetal homozygous carriers of the translocation. We, therefore, suspect that Caspr5-2 disruption leads to dysfunction at the cellular level rather than at the level of organ development.
authors.affiliation: Deutsches Krebsforschungszentrum, 69120 Heidelberg, Germany. d.weichenhan@dkfz-heidelberg.de
authors.forename: Dieter
authors.initials: D
authors.lastname: Weichenhan
authors.forename: Walther
authors.initials: W
authors.lastname: Traut
authors.forename: Christina
authors.initials: C
authors.lastname: Göngrich
authors.forename: Heinz
authors.initials: H
authors.lastname: Himmelbauer
authors.forename: Lüder
authors.initials: L
authors.lastname: Busch
authors.forename: Hannah
authors.initials: H
authors.lastname: Monyer
authors.forename: Heinz
authors.initials: H
authors.lastname: Winking
mesh_terms: D000818:Animals; D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics* / Q000378:metabolism; D002874:Chromosome Mapping; D022202:Chromosomes, Artificial, Bacterial / Q000235:genetics; D003433:Crosses, Genetic; D005260:Female; D005804:Genes, Lethal; D005838:Genotype; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D051379:Mice; D009154:Mutation; D014178:Translocation, Genetic
chemical_list: D015816:Cell Adhesion Molecules, Neuronal; C491322:Cntnap1 protein, mouse